The lymphatic system: how it works, lymphoma and other causes of swollen lymph nodes, and how to safeguard your health – experts explain

The lymphatic system is a network of tissues, vessels and organs working together to move a colourless, watery fluid called lymph back into the bloodstream.

Essentially a drainage network, it forms the foundation of our health and wellness.

About 20 litres (40 pints) of plasma flow through the body’s arteries, blood vessels and capillaries every day, delivering nutrients to cells and collecting their waste products.

Most of the plasma returns to circulation through the veins.

But about three litres seep through the capillaries into the body’s tissues.